Michael Mullan an independent food and beverages professional discusses how to control the hardness of ice cream and gelato.

Frozen dairy desserts such as ice cream and gelato are consumed when the product is in the partly frozen state. They rely on a combination of mix composition, processing conditions and temperature-control during freezing and final product storage to achieve a product of the required texture.

The manufacturing process for ice cream and gelato is similar and involves the preparation of a liquid mix; whipping and freezing this mix dynamically under high shear to a soft, semi-frozen slurry; incorporation of favouring ingredients to this partially frozen mix; packaging the product; and further freezing (hardening) of the product under static, quiescent conditions.^[1]

Gelato while similar to ice cream has a lower overrun (reduced volume of air incorporated), reduced fat content, tends to be sweeter and softer and generally offers more intense fruit flavours.

In this article we will explore how food scientists and technologists can vary the mix composition and thus control the hardness or "scoopability" of ice cream, gelato and similar products. The volume of air added during freezing (overrun) and the type and concentration of emulsifier can also affect hardness but will not be considered further as these effects while important are generally less significant than the concentration of sweeteners used and the serving temperature. Because hardness and sweetness are related, and sweetness is only briefly discussed readers may wish to explore this area further.^[2]

There is an extensive range of flavoured ice creams (Plate 1) however there is frequently a marked difference in hardness between flavours in the UK, Ireland and the US compared with gelato in Italy e.g. the chocolate flavour is often harder, more difficult to scoop, than the vanilla or strawberry flavours.

In recent years there has been a significant increase in the number of specialist ice cream shops / parlours or gelateria in the UK. Many of these gelateria owners require ice cream or gelato that is of consistent sweetness and hardness or resistance to scooping, also called dipping in the U.S. Consequently food technologists should have a good understanding of how to formulate an ice cream mix to control the hardness and sweetness of the ice cream.

独立食品和饮料专业人士 Michael Mullan 讨论如何控制冰淇淋和冰淇淋的硬度。

当产品处于部分冷冻状态时，会食用冰激凌和冰淇淋等冷冻乳制品甜点。他们依靠混合成分、加工条件和冷冻和最终产品储存期间的温度控制来获得所需质地的产品。

冰淇淋和冰淇淋的制造过程相似，都涉及到液体混合物的制备。在高剪切下动态搅打和冷冻该混合物，形成柔软的半冷冻浆液；在这种部分冷冻的混合物中加入有利的成分；包装产品；并在静态、静止条件下进一步冷冻（硬化）产品。^{[ 1 ]}

Gelato 虽然与冰淇淋相似，但具有较低的溢出量（减少的空气量）、减少的脂肪含量、更甜、更柔软，并且通常提供更强烈的水果风味。

在本文中，我们将探讨食品科学家和技术人员如何改变混合成分，从而控制冰淇淋、冰淇淋和类似产品的硬度或“可铲性”。冷冻（溢出）过程中添加的空气量以及乳化剂的类型和浓度也会影响硬度，但不会进一步考虑，因为这些影响虽然重要，但通常不如使用的甜味剂浓度和食用温度那么显着。因为硬度和甜度是相关的，而甜度只是简单的讨论，读者不妨进一步探索这个领域。^{[ 2 ]}

口味冰淇淋种类繁多（图版 1），但与意大利的冰淇淋相比，英国、爱尔兰和美国的口味之间的硬度通常存在显着差异，例如巧克力口味通常更硬，更难舀取，比香草或草莓的味道。

近年来，英国专业冰淇淋店/店或冰淇淋店的数量显着增加。这些冰淇淋店老板中的许多人要求冰淇淋或冰淇淋具有一致的甜度和硬度或抗舀，在美国也称为浸渍因此食品技术人员应该很好地了解如何配制冰淇淋混合物以控制硬度和甜度的冰淇淋。